James Wan must feel like he’s got something to prove. The filmmaker has had success more than once (“Saw” and “Insidious”) in a horror genre that has been obnoxiously stagnant in recent years (everything is either a haunted house or exorcism film). “The Conjuring” is both, so more of the same for Wan.

There’s almost nothing original about “The Conjuring.” We’re talking spot-the-cliché drinking game unoriginal. So it begs the question: did Wan want to prove he could make a great horror film from overused genre hallmarks, or does he just have no interest in innovative filmmaking? Probably a little of both.

The one unique angle of “The Conjuring” comes in the form of two non-fictional protagonists. Ed and Lorraine Warren are two paranormal investigators/demonologists who claim to have investigated upwards of 10,000 hauntings from the ’50s to the ’80s. They are most known for investigating the famous “Amityville horror” case that inspired two film versions (and frankly, “The Conjuring” is almost like a third).

Patrick Wilson and Vera Farmiga star as the Warrens, who are brought in to investigate disturbances in the new Rhode Island country home of the Perron family. Carolyn and Roger Perron (Lili Taylor and Ron Livingston)and their five girls have experienced a number of phenomena (moving doors, rotting flesh smell, a little ghost boy who’s befriended the youngest daughter, etc.), and the Warrens can tell immediately when they enter that something particularly bad is here.

Like any effective horror film, the build-up is painfully slow so that your mind moves into darker places than the film is going for the first half hour or so. All the occurrences happen predominantly at 3:07 in the morning, so the film cycles between day and night scenes in a way that’ll drive you mad in the way that it teases a reprieve but that goes straight back into someone following a suspicious noise behind a door or under the bed.

The scares of the film escalate too, from suspense techniques meant to elicit anxious anticipation of bigger scares to all-out fantastical mayhem, including a gruesome exorcism. It does so with a good measure of tact, but “The Conjuring” could have played the mystery angle longer than it does in order to earn some more points.

One of the absolute standouts is Farmiga’s performance as Lorraine, who is among the best characters I can ever recall in a genre horror film. A clairvoyant, she easily sees demon spirits and can sense what’s going on. Farmiga gives Lorraine so much grace and courage that we clearly sense she is a woman who has seen a lot. At the same time, she gets frightened when we expect her to as well. She has some a subplot involving a traumatic past experience and her relationship to her daughter, but the film leaves us hanging by not finishing those arcs, presumably in a cocky “save it for the sequel” way.

A scenario in which some people are completely unimpressed by “The Conjouring” while others consider it great seems a likely outcome. The market is stale for new horror ideas, while studios making horror films understand that familiarity gets people into the theater. So those looking for something novel won’t find it, but those who want the tropes of the genre will be more than pleased.

Wan in particular knows all the tropes, and better than anyone, he milks them for all of their worth. He does so with incredible technical prowess, but more importantly, the ability to understand the audience’s instincts — what they’re thinking and expecting.

For fans who know exactly what Wan offers them, consider “The Conjuring” on par with “Insidious,” only a little more cliché and with a more intriguing mystery.